The use of wireless local area networks (WLANs) offers great flexibility for the users of communication devices such as computers, tablets, smartphones, etc. In order not to enable any communication device to connect to a WLAN network and to have access to data exchanges occurring via the WLAN network, security protocols are implemented. Ensuring the security of the WLAN network must however not be done to the detriment of simplicity of configuration.
For example, in the context of a Wi-Fi (registered trade mark) network, the WPS (“Wi-Fi protected setup”) protocol can be used. The aim of the WPS protocol is that the configuration phase for protecting a Wi-Fi network should be simple, and therefore accessible to users without any special knowledge of communication network configuration. The WPS protocol proposes at least three ways of enabling a communication device to pair with a wireless access point (WAP), that is to say to recover from said wireless access point WAP encryption keys allowing to communicate in a secured manner in the Wi-Fi (registered trade mark) network: the PIN (personal identification number) pairing procedure, the PBC (push-button configuration) pairing procedure and the NFC (near-field communication) pairing procedure.
The PIN pairing procedure is based on a PIN code supplied by the communication device seeking to connect to a Wi-Fi (registered trade mark) network; this code is then entered by a user via a user interface of the wireless access point WAP. Conversely, it is also possible to enter a PIN code supplied by the wireless access point WAP via a user interface of the communication device seeking to connect to the Wi-Fi (registered trade mark) network. However, in 2011, the researcher Stefan Viehbock revealed an important fault in the PIN pairing procedure, which now makes it non-recommended.
The PBC pairing procedure is based on the fact that the user presses a button, whether it be physical or virtual, both on the wireless point WAP and on the communication device to be connected to the Wi-Fi (registered trade mark) network protected. The PBC pairing procedure is thus such that the wireless access point WAP thus provides, during a period of time of predefined duration and to any communication device making a request for it, a systematic pairing authorisation.
The NFC pairing procedure is based on the fact that the user moves the communication device to be connected to the Wi-Fi (registered trade mark) network close to the WAP access point in order to establish near-field communication. The NFC pairing procedure is thus such that the access point WAP thus provides, to any communication device making a request for it by near-field communication NFC, a systematic pairing authorisation. This solution is particularly practical for small communication devices, e.g. those that are held in the hand.
In the context of PBC and NFC pairing procedures, when the access point WAP creates a plurality of cells according to a plurality of respective spectral bands (e.g. at 2.4 GHz and 5 GHz in the context of Wi-Fi (registered trade mark)) networks, the wireless access point WAP does not have control of the spectral band via which a communication device will seek to pair. Said communication device may then be paired to the wireless access point WAP via a cell that happens to have a less good performance than another cell created by said wireless access point WAP.